SO, THIS THREAD IS ABOUT A SPELL USED IN HARRY POTTER?

Riddikulus!

Word Origin: From the Latin ridiculus (facetious, laughable)
Purpose: This incantation is used to get rid of a Boggart - a creature that assumes the form of a person's greatest fear. Prior to casting the spell, the wizard/witch must visualize the Boggart doing or being something humorously ridiculous. The laughter this causes will banish the Boggart.

Example: In Harry Potter and the Goblet of Fire, while in the Triwizard maze, Harry successfully cast this spell upon a boggart .